Seal device

ABSTRACT

According to the invention there is provided a seal device ( 1 ), for example for use with an obturating device such as a cone value ( 2 ) of an intermediate bulk container ( 3 ) (IBC) which is set down at a discharge station ( 4 ) with a sealing arrangement therebetween so that when a lifting member such as a cone ( 5 ) of the discharge station ( 4 ) is operated to raise the cone valve ( 2 ) and open a flow path for flowable material such as a powder from the IBC through the discharge station ( 4 ). In order to provide a seal, the seal device ( 1 ) of an elastomeric material, has an annular seal surface ( 6 ) and means ( 7 ) which enhances sealing by the sealing surface ( 6 ).

The invention relates to a seal device, particularly to such a devicewhich is used in material handling apparatus such as an IntermediateBulk Container (IBC), also referred to as a tote container.

Such apparatus is often used for the storage, transport, transfer andgeneral handling of flowable particulate material, which may be used inthe food, pharmaceutical and nuclear industries. Whatever the use of thematerial, it will be understood that it is important to avoidcontamination of the surrounding environment on straight environmentalgrounds, and on health grounds.

To that end, outlets of the IBCs, and stations at which they are whollyor partially emptied, have an arrangement of seals, often known as α-and β-seals, and these are generally extremely effective. However, thereare sometimes formed crevices or niches in which material can collect,particularly when an IBC is mounted on a discharge station, and fromwhich material can leak into the environment when the IBC and stationseparate.

It is an object of the invention to seek to mitigate this disadvantage.

According to a first aspect of the invention there is provided a sealdevice, comprising a seal having an external annular sealing surface,and means to enhance sealing by the sealing surface.

The means may be internally of the sealing surface. This provides forsealing over the length of the sealing surface.

The means may comprise a strengthening member spaced from the seal. Thisconstruction seeks to reinforce the seal against non-sealing at thelateral extremities of the sealing surface.

The seal may comprise respective seating parts at opposite ends of thesealing surface, and the strengthening member may extend between thesealing parts. This provides for support for the extremities of thesealing surface, particularly when the strengthening member may comprisean annular member, which may be a frusto-conical annular member.

The annular member may comprise a material which may be relatively stiffcompared with the material of the seal. This assists in strengtheningthe seal surface against collapse.

The annular member may comprise a semi-rigid plastic material. This is arelatively inexpensive but effective construction.

The material may comprise a polycarbonate material.

The means to enhance sealing may be incorporated with the seal during amoulding process therefor.

The means to enhance sealing may also be externally of the sealingsurface. This provides for enhanced sealing.

The seal may comprise respective seating parts at opposite ends of thesealing surface, and the means may extend from one of the seating partsin a direction externally of the scaling surfaces. This constructionprovides for enhanced sealing over the sealing surface in use,particularly when the means may comprise a flexible member which mayextend from an upper in use seating part in the direction of andoverlying the scaling surface.

The member may be formed integrally with the seal. This provides for arelatively simple construction.

The member may be flexible enough to be folded or bent to lie in aposition directed away from the sealing surface. This provides foreffective sealing in use.

According to a second aspect of the invention there is providedapparatus including a seal device as hereinbefore defined.

The apparatus may comprise a cone valve for a container for handlingflowable material.

The container may comprise an IBC or tote container.

A seal device and apparatus embodying the invention are hereinafterdescribed, by way of example, with reference to the accompanyingdrawings.

FIG. 1 is a transverse sectional view of part of a first embodiment ofseal device according to the invention;

FIG. 2 shows a schematic view of a discharge station of materialhandling apparatus including the seal device of FIG. 1 to a reducedscale;

FIG. 3 shows a transverse sectional view of part of a second embodimentof seal device according to the invention; and

FIG. 4 shows a schematic view of a discharge station of materialhandling apparatus including the seal device of FIG. 3, to a reducedscale.

Referring to the drawings there is shown a seal device 1, for examplefor use with an obturating device such as a cone valve 2 of anintermediate bulk container 3 (IBC) which is seat down at a dischargestation 4 with a sealing arrangement therebetween so that when a liftingmember such as a cone 5 of the discharge station 4 is operated to raisethe cone valve 2 and open a flow path for flowable material such as apowder from the IBC through the discharge station 4. In order to providea seal, the seal device 1 of an elastomeric material, has an annularseal surface 6 and means 7 (FIG. 1) or 8 (FIG. 3) which enhances sealingby the sealing surface 6.

The means 7 (FIGS. 1, 3) is an annular ring which in the embodiment isof relatively stitler material than that of the surface and whichsuitably is of polycarbonate, a semi-rigid plastic, in the embodiment.The ring 7 is interiorly mounted with respect to the sealing surface 6,and extends between radially inner parts 9, 10 of the seal at oppositeparts of the sealing surface. The ring 7 is a separate component isincorporated in the seal device 1 after moulding of the seal device, andessentially maintains the parts 9,10 in their desired positions so thatthey do not move inwardly and thus do not create crevices in which thematerial can collect. Thus the sealing surface 6 is used for fullsealing effect.

Stated in another way, the ring 7 forces the parts 9, 10 apart,maintaining the correct seal device 1 profile during use or bonding.Thus if the seal device 1 comes out of position, if used in a looseseal, or there is variation during bonding at the assembly stage if usedas a bonded seal, the seal device 1 maintains the correct profile.

The ring and seal device 1 could be assembled integrally, in other wordsthe ring could be incorporated in the seal device 1 during moulding ofthe seal device.

Referring now to FIGS. 3 and 4, in the embodiment of seal device 1 shownthe means 8 is an integral ring which extends exteriorly from the partto overlie the sealing surface 6.

In use, the means 8 which is an extension or “feather edge” is flexibleand can be folded back on itself in use to prevent ingress of materialinto a space therebelow to lie along a wall at the outlet 11.

The means 8 thus provides an external lip which in an intermediateposition as the IBC is lowered is capable of arresting product flowwithout damage to the material being handled, as shown in FIG. 3. In thefully lowered position of the IBC, FIG. 4, the means 8 prevents materialfrom being trapped between the outlet 11 and the sealing surface 6 ofthe seal device 1 becomes operative for sealing.

It will be understood that the seal device may include both means 7 and8.

What is claimed is:
 1. A seal device for a container outlet, comprisingan annular seal formed from a resilient material having an externalannular sealing surface and two axially spaced, radially inwardlydirected flanges, and means for preventing movement of the flangestowards one another disposed to enhance sealing by the sealing surface.2. A seal device according to claim 1, the means being internally of thesealing surface.
 3. A seal device according to claim 2, wherein themeans comprises a strengthening member spaced from the sealing surface.4. A seal device according to claim 3, the strengthening memberextending between the flanges.
 5. A seal device according to claim 4,the strengthening member comprising an annular member.
 6. A seal deviceaccording to claim 5, the annular member comprising a frusto-conicalannular member.
 7. A seal device according to claim 6, the annularmember comprising a material which is relatively stiff compared with thematerial of the seal.
 8. A seal device according to claim 7, the annularmember comprising a semi-rigid plastic material.
 9. A seal deviceaccording to claim 8, the material comprising a polycarbonate material.10. A seal device according to claim 1, the means being incorporatedwith the seal during a moulding process therefor.
 11. A seal device fora container outlet, comprising an annular seal formed from a resilientmaterial and having an external annular sealing surface, and a flexiblemember, which extends from an upper, in use, part of the sealing surfacein the direction of and overlying the sealing surface.
 12. A seal deviceaccording to claim 11, the member being formed integrally with the seal.13. A seal device according to claim 12, the member being flexibleenough to be folded or bent to be in a position directed away from thesealing surface.
 14. A seal device for a container outlet, comprising anannular seal formed from a resilient material and having an externalannular sealing surface, the device having two axially spaced, radiallyinwardly directed flanges, means for preventing movement of the flangestowards one another disposed to enhance sealing by the sealing surface,and a flexible member which extends from an upper, in use, part of thesealing surface in the direction of and overlying the sealing surface.15. An apparatus including a seal device for a container outletcomprising an annular seal formed from a resilient material having anexternal annular sealing surface and two axially spaced, radiallyinwardly directed flanges, and means for preventing movement of theflanges towards one another disposed to enhance sealing by the sealingsurface.
 16. apparatus according to claim 15, comprising a cone valvefor a container for handling flowable material.
 17. Apparatus accordingto claim 16, the container comprising an IBC or tote container.
 18. Anapparatus including a seal device for a container outlet, comprising anannular seal formed from a resilient material and having an externalannular sealing surface, and a flexible member which extends from anupper, in use, part of the sealing surface in the direction of andoverlying the sealing surface.